Transformer



Oct. 21 1924- J. LEDWINKA TRANSFORMER Filed May 19. 1919 Patented Oct. 21, 1924.

UNITED STATES PATENT OFFICE.

JOSEPH LEDWINKA, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOB TO EDWARD G. BUDD MANUFACTURING COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A COR- POBATION OF PENNSYLVANIA.

TRANSFORMER.

Application filed May 19, 1819. Serial No. 298,086.

To all whom it may concern:

Be it known that I, JOSEPH LEDWINKA, a citizen of the United States, residing at Philadelphia, county of Philadelphia, State of Pennsylvania, have made a certain new and useful Invention in Transformers, of which the following is a specification.

This invention relates to transformers.

The object of the invention is to provide a construction of transformer which is simple, economical to manufacture, and easily assembled.

A further object of the invention is to provide a transformer of such construction as to facilitate the easy removal and replacement of the transformer coils.

Other objects of the invention will appear more fully hereinafter.

The invention consists substantially in the construction, combination, location and relative arrangement of parts, all as will be more fully hereinafter set forth, as shown in the accompanying drawing, and finally pointed out in the appended claims.

In the drawing:

Fig. 1 is a view in perspective showing a transformer structure embodying the principles of m invention.

Fig. 2 is a view in section on the line 2, 2, Fig. 1, looking in the direction of the arrows.

Fig. 3 is a detached detail view in perspective showing one form of laminated core plates employed in connection with a transformer embodying my invention.

Fig. 4 is a view similar to Fig. 3 showing a modified form of laminated core plate.

The same part is designated by the same reference numeral wherever it occurs throughout the several views.

In the construction of transformers it is a common practice to build up the core of sheets or laminae of sheet metal which are suitably out out to form a central extension around which the transformer coils are wound. In assembling the laminae it is a customary practice to lap the laminations or plates the one upon the other. This practice, however, necessitates the taking apart of the entire transformer core whenever it becomes necessary to repair, renew or replace the coils of the transformer. It is among the special purposes of my present invention to provide a construction of trans" former which is exceedingly simple and economical to manufacture, which is strong and sturdy, and which permits the renewal, repair or replacement ofthe transformer coils without removing or. disturbing individual plates of the laminated core. In carrying out my invention I propose to assemble the transformer core in separableand removable halves or sections, each half or section being composed of superposed laminations or plates, and each section or half carrying a portion of the core projection around which the coils are wound so that by merely separating the two sections or halves of the core structure without disturbing the individual plates or laminations thereof access may be gained to the coils for repair, renewal or replacement thereof.

In the drawing: Reference numeral 5, Fig. 1, designates generally the transformer core. This core is made up of sections or halves indicated generally at 6', 7, Fig. 2. Each section or half is built up of laminations or plates 8, 9, or 10, 11, see Figs. 3 and 4, for example, the section or half 6 of the core is built up by a series of plates or laminations,- as for example, 9, see Fig. 3, or 11, see Fig. 4, each plate or lamination being stamped out of metal with end portions 12 and a central portion 13. Likewise the other section or half 7 of the transformer core is built up of corresponding or cooperatinglaminations or plates, as for example, 8, see Fig. 3, 10, see Fig. 4, each plate or lamination having end portions 12 and a central portion projection 13 corresponding exactly with the end portions and central projections 12, 13, of the section 6, the end project ons 12 and central projections 13 of the one section or half of the core adapted to be brought into register and contact relation with the end projections 12 and central projections 13 of the other sec tion or half of the core when the two sections or halves are brought together.

If desired, and as shown in Fig. 3, the abutting edges of the end and central projections 12, 13, lie flatwise against each other when brought together by assembling the two halves or sections of the core together. I do not desire, however, to be limited or restricted to a straight line contact of the abutting edges or surfaces of the end and central projections 12, 13. For example, as

shown in Fig. 4, the abutting edges of the laminations or plates 10, 11, or of the end and central projections 12, 13, thereof, are formed with interengaging or interlocking steps and seats 'as indicated at 14. This arrangement increases the area of each contact of the assembled plates of one section or half of the transformer against the edges of the sections or plates of the other section or half of the transformer, and also the ar rangement shown in Fig. 4 aids in centering the sections or halves of the transformer when brought into assembled relation with respect to each other. After building up the laminations or plates to form one section or half of the transformer the assembled laminations for such half are clamped together between clamp plates 15, 16, applied respectively to opposite sides of the assembled laminations or plates forming the section or half of the core.

The two plates 15, 16, between which the assembled laminations or plates are clamped are formed with corresponding lugs 17, through which extend clamping bolts 18, which serve to clamp and secure the assembled sheets or laminations together to form one unit of the transformer core. The clamp plates 15, 16, are also provided with lugs 19 cooperating with each other to afford means for clamping the one unit of assembled laminations or plates to the other unit of assembledlaminations or plates by means of the bolts 20.

It will be observed that by this structure and arrangement the complete transformer is made up of separable units, the units be-. ing detachably clamped or secured together by clamp bolts located externally to the laminae, and that each unit is composed of sheet metal plates or laminae which are held or clamped between clamping plates applied to opposite sides of the stack or pile of laminae and bolted together by bolts which are likewise external to the laminae. In this way I avoid the necessity of punching bolt holes through the laminae and of successively stringing the individual laminations upon clamping bolts, and hence I am enabled to greatly facilitate the work of .assembling. and disassembling the structure. I also avoid the very serious objection of eddy currents and resulting heat effects in the mass of the transformer core due to the pressure in the body thereof of clamp bolts.

Any desired or preferred arrangement of transformer coils may be employed. Merely for illustrative purposes I have shown three coils 21, 22, 23, said coils being encircled around the central projections 13 of the laminations. It is to be understood, of course, that any desired arrangement of coils may be employed.

With a construction such as above described, when it is desired to repair, renew placed when the transformer may again be assembled by merely bringing the two halves or sections together and clamping them together with the clamp bolts 20 as will be clearly understood.

Many variations and changes in the details of construction and arrangement will readily occur to persons skilled in the art and still fall within the spirit and scope of my invention. I do not desire therefore to be limited or restricted to the exact details shown and described, but having now set forth the objects and nature of my invention and a construction embodying the principles thereof, what I claim as new and useful and of my own invention and desire to secure by Letters Patent is,-

1. In a transformer, unit sections or halves, each consisting of sheets or laminations formed with end and central projections and piled the one upon the other, clamp plates applied to opposite faces of the stack or pile of laminations, and having ears extending beyond the edges of the laminations, said ears bolted togetherto clamp the laminations between said clamp plates, to form the unit, and means for detachably clamping together the units with the end and central projections of the laminae of the one section or half abutting edgewise against those of the laminae of the other section or half, the abutting edges of the laminae having interen'gaging steps or seats.

2. In a transformer, unit sections or halves, each consisting of a plurality of sheets or laminations piled the one upon the other, each lamination having in one edge thereof laterally projecting portions at each end and at an intermediate point between said ends, said intermediate projections con stituting the core part of the transformer to receive the transformer coils, clamp plates applied to opposite faces of each stack or pile, means disposed outside of the stack 01' pile of laminations to hold said clamp plates together to form the unit section, and means to detachably clamp two of such units together with the end and intermediate projections of the laminae of the one unit abutting edgewise against the corresponding projections of the laminae of the other.

3. A transformer comprising a pair of separable units, each unit including a plurality of lamina. means disposed wholly outside of said laminae for clamping them to gether into a stack or pile, and means also disposed outside of said units for detachably securing them together with the lamina: of the one unit fitting edgewise against those of the other unit.

4. A transformer comprising a coil and a laminated core therefor, said core made up in independent separable units, each unit having a plurality of laminations stacked or piled upon each other, clamp plates applied to the top and bottom of said stack or pile, means disposed outside of the stack or pile and engaging said plates to clamp the same upon the laminations to hold the latter, and means also disposed outside of said units to detachably clamp them together.

5. A transformer comprising a coil and independently assembled and separable core units for said coil, each unit including a stack or pile of laminations, means disposed wholly externally to the stack or pile for clamping the Ia-minations contained therein together, and means also disposed externally to said stacks or piles to detachably clamp the clamping means of said core units together.

6. A transformer comprising a coil and independentlv assembled core units therefor, each unit including a stack or pile of laminations of E-shape in outline, clamping plates applied to the opposite ends of each stack or pile, clamping bolts disposed outside of the stack or pile of laminations to clamp and hold said plates with the laminations between them, and means to detachably clamp together the clampin'g means of the said units with the corresponding edge por; tions of the E-shaped laminations of the units abutting against each other.

In testimony whereof I have hereunto set my hand on this 7th day of May, A. D. 1919.

JOSE H LEDWINKA 

